Hydraulic starting system for internal combustion engines



United States Patent M HYDRAULIC STARTING SYSTEM FOR :INTERNALCOMBUSTION ENGINES Lucien I. Pihiel, YValley Stream, N. Y., lassigner,by mesne assignments, to American Bosch Arma Corporation, Hempstead N.Y., -a corporation of New 'York Application March 29, 1956, Serial No.574,778

6 Claims. (Cl. 12S-179) The present invention relates to anautomatic'hydraulic starting system for an internal combustion engine.lIt is illustrated and described in connection with a system of thistype which drives an electric generator used for auxiliaryr or emergencypower. The invention is particularly useful in a system of thischaracter which includes a hand pump for restoring hydraulic pressure inthe event that the engine should fail to start before the hydraulicpressure is spent.

kIt is common practice to provide an automatic starting system for anengine driven emergency generator in-which the energy for operation ofthe starter which cranks the internal combustion engine is derived fromstorage batteries. With systems of this type, in the -event of failureofthe main generator, the only available vsource of electrical energyfor cranking the auxiliary generator consists of the storage batteries.lf diiculty is experienced in starting the auxiliary generator, andassuming nthe batteries are fully charged, they may vnevertheless becomedischarged in the course of repeated ineffective crankings of the enginewhich fail to start the generator. Under such conditions with thebatteries discharged, no electrical energy whatever is available. Whenlthe emergency generator engine is of such large size that it cannot becranked by hand, an extremely -serious situationprevails in isolatedinstallations, such as in shipboard power systems.

The present invention provides -an automatic 'electrohydraulic actuatingsystem for a starter'of the above type and which is operated by pressurefluid 'stored in an-ac cumulator which is a conventional velement of thestarter per se. When power failure occurs at the main bus,theelectro-hydraulic system automatically causes cranking of the emergencygenerator engine. If the engine `fails to start and the pressure uid inthe accumulator is spent withoutstarting the engine, manually VoperableValves are provided which permit the 'accumulator pressure to berestored 'by means of the usual hand pump.

Various other features and advantages of theinvention vwill becomeapparent upon reading the -following specilication together with theaccompanying drawing --forming a part hereof. k

Referring tothe drawing:

'Figure l is a combined electricaland hydraulic diagram of a systemembodying the invention; and

lFigure 2 is a fragmentary View showing a modified form of the system ofFigure 1.

In Figure l a-main engine 10 drives a main alternator or direct currentgenerator 111 `through a mechanical fcoupling indicated by the dottedline 13. The Amain .gen-

erator 11 normally supplies power continuously Ito-conductors 14 whichconstitute the -main bus. VBranchcircuit conductors 1-6 extend from mainbus conductors t1-4'to1a load (not shown) which is not yrequired to`=beenergized in the event of failure of the ymain generator`121,;'failure of its driving engine 10 or other circumstanceslproducing power failure at conductors 14 of the Amainbus.

A `main -bus contactor designated generally -as 17 v4is `'ventionaldesign which is not illustrated in detail.

, 2,845,916 Patented Aug. 5, 1958 lCC provided with an operating winding19 which is shown -a load (not shown) which is of'major importance andwhich is required to be energized during power failure at -the main busconductors l14.

An emergency power contactor 24 is provided with two poles comprisingnormally ,open contacts 25 which may be closed by energization of itsoperating winding 26.

The operating winding 26 is connected to the outputterminals of anemergency generator 28. The emergency generator 28 is driven by anormally inoperative internal combustion engine 29 connected thereto bya mechanical -coupling indicated by the dotted line 31.

Afhydraulic starter 32 is arranged to start'the engine 29 through theusual self-engaging and self-disengaging coupling indicated by thedotted line 34. The 'hydraulic starter 32 comprises a suitable hydraulicymotor of con- The starter32 may be placed in operation by leftwardmove- Vment of a control lever 35. Normally, the control lever `35 ispositioned toward the lright as shown inthe drawing. An accumulator 37,which is preferably ofthe springpiston type, is connected to maintain aconstantly available supply of hydraulic fluidunderpressure'at-thestarter '32-via hydraulic lines 38 and 40. Spentpressure fluid is returned to a reservoir 41 via return lines 43and 44.

-Pressure is maintained in accumulator 37 while engine 29 is running bymeans of asuitable engine driven pump 46 connected to the output shaftof engine 29 througha power take-olf indicated bythe dotted vline 47.The Vinlet to engine driven pump 46 is connected to the bottom ofreservoir 41 through afilter 49 included in'a fluid 'supply line 50. Ifrequired, to Aprevent back-flow through engine `driven pump 46, acheck'valve 52 may be-provided mediately adjacent to the pump outlet.

A-hand pump-53 is provided and is'conncted in multiple with the enginedriven pump 46 by inlet and outletliues 5S and 56, respectively. Thehand pump 53 -will `'inherently Aprevent backow so that no check valveis required.

A'barrel S4 is provided having a front end cap 54a and a'rear end cap54h. A tubular insert 54e forms acylinder which is designated as 58.Cylinder A58 is formed as the 4front end of barrel 54 and is `providedwith a rod-'like piston 59 which is slidable in the insert 54e .andWhich extends throughout the length of the barrel. Barrel 54 is formedwith a peripheral slot 60 at the rear -end thereof. A rigid, laterallyextending arm 61 travels in said slot 60 and is connected to a centralportion of pislton 59. Arm 61 is connected, at its outward ylateralextending end, to a horizontally extending -control -rod v62. Acompression spring 65 is disposed within the rear end of 'barrel 54 andhas as its terminals the rear end -cap `54b 4and lthearm 61.Accordingly, the arm 61 is lnormally maintained in a leftward position,the spring 65 thereby -functioning as a restoring means for the controlrod .62 and the piston 59 and will be shown hereinafter.

Control rod 62 is linked to the starter control lever '35 so thatleftwardmovernent of control rod 62 will operate -thefhydraulic starter32. A manually operable hand knob `64 is fixed to the right hand end ofcontrol rod 62 for initiating operation of the starter 32 manuallyWhenever desired. The control rod 62 and piston 59 are "both `yieldinglyurged toward the right by the restoring means lexemplified by thehelical compression spring v65.

The piston 59'isforced to the left for starting .engine 29 vthy-pressureuid supplied to the .righthand end of cylinder S8 through a hydraulicline 67. The cylinder line 67 extends to a junction between inlet andoutlet control solenoid valves 63 and 7l) respectively. The solenoidvalves 68 and 70 are provided with operating windings 71 and 73 whichare connected in parallel and are both normally continuously energizedfrom the conductors 72 of the emergency bus through the normally closedcontacts 74 of a manually operable starting switch 76. control valve 68is closed when its winding 71 is energized and thus normally preventsthe flow of pressure fluid to cylinder 5S. Outlet control valve 70 isopen when its operating winding 73 is energized and therefore normallyconnects the cylinder 58 with the reservoir 4l. through a return line 77which merges with return line 44 permitting compression spring 65 tohold control lever 35 in its normal inoperative position.

Pressure fluid is supplied via a hydraulic line 78 to inlet controlvalve 68 through a manually operable inlet valve 79 which is ordinarilykept open. Ctutlet valve 70 is bypassed by a manually operable outletvalve 80 which is ordinarily kept closed. These manual valves 79 and 80are used only while restoring accumulator pressure by means of hand pump53 in the absence of electric power for operation of the solenoid valves68 and 7 il. With no power available at emergency bus conductors 22,solenoid valve windings 71 and 73 are permanently de-energized, Underthese circumstances, valve 79 is closed manually so that no pressure uidwill be drawn from accumulator 37 until a sutlicient pressure has beenbuilt up by hand pumping to operate the starter 22 electively and crankthe engine 29. Valve 8G is opened manually to permit piston 59 to moveto the right. A pressure gauge 32 is connected to line 78 to permitobservation of the accumulator pressure so that unnecessary hand pumpingmay be avoided.

In operation, when there is a power failure at main bus conductors 14,the solenoid valve operating windings 71 and 73 become de-energized.Inlet valve 68 then opens admitting pressure iluid from line 78 to theline 67 extending to cylinder 58. Simultaneously, outlet valve 70 closespreventing the direct flow of pressure uid to reservoir 41. Pressure uidis thus fed to the right hand end of cylinder 58 forcing piston 59 tothe left. At the same time, the main bus contacter 19 releases therebydisconnecting and isolating the emergency bus conductors 22 from themain bus conductors 14.

As piston 59 moves to the left, control rod 62 also moves to the leftcausing the control lever 35 of hydraulic starter 32 to move to itsoperative position whereupon the starter 32 cranks the emergency engine29. If the engine 29 starts in response to cranking, emergency generator28 immediately builds up voltage and operates the emergency buscontactor 24, connecting the emergency generator 28 to the emergency busconductors 22. All loads connected to the emergency bus conductors 22are then re-energized along with the solenoid valve windings 71 and 73.Upon energization of solenoid valve windings 71 and 73, the inlet andoutlet valves 68 and 70 resume their respective closed and lopenpositions so that cylinder 68 is disconnected from pressure line 78 andconnected to return line 77. Piston 59 and control lever 35 then resumetheir normal inoperative positions under the influence of compressionspring 65. Failure of emergency generator Voltage at emergency busconductors 22 will similarly cause recranking of emergency engine 29.

If the emergency engine 29 repeatedly fails to respond to cranking forany reason, the pressure in accumulator 37 will drop to a point wherecranking is no longer possible. Manual inlet valve 79 is then closed toconserve pressure fluid. Manual outlet valve 80 is temporarily openedlong enough to permit spring 65 to bring control lever 35 to itsinoperative position, thereby shutting olf any drain on accumulator 37through starter 32. Hand pump 33 is then operated manually untilpressure gauge Inlet 82 indicates adequate pressure has been built upfor eiective cranking operation of the hydraulic starter 32. Manualinlet valve 79 is then opened and the cranking operation repeated. Thiscranking operation can be repeated from time to time indefinitelybecause hand pump 53 is always available to build up the necessaryhydraulic pressure in accumulator 37.

During normal operation, the emergency engine may always be startedmanually for test purposes by operation of manual starting switch 76which de-energizes the solenoid valve windings 71 and 73 in the samemanner as a power failure. When testing under these conditions,contactor 24 may advantageously be temporarily blocked open or otherwiserendered inoperative until after cornpletion of the test.

Figure 2 shows a modified form of the invention in which a manualstarting switch 82 is provided for remote operation of starter 32whenever desired without regard to power failure. Inlet and outletvalves 83 and S5 are connected to lines 78, 67 and 77 as in Figure l andthe operation is the same, except that engine 29 may drive some loadother than a generator, such as a propeller shaft or pump, for example.

The manual starting switch 82 is provided with normally open contacts86. The inlet valve S3 is provided with a normally de-energizedoperating winding 88 and the valve 83 is normally closed. When winding88 is energized, inlet valve S3 opens admitting pressure iluid from line78 to the line 67 which extends to cylinder 58. The outlet valve 85 isprovided with a normally de-energized operating winding 89. When winding89 is energized, outlet valve 85 closes shutting off cylinder line 67from return line 77.

The operating windings 8S and S9 of inlet and outlet valves 83 and 85are shown connected in series for simultaneous energization by a sourceof current indicated as a battery 91. Thus, whenever the starting switch82 is manually closed, engine 29 will be cranked. Because electric poweris not required to maintain the valves 33 and S5 in their normalpositions, the manual valves 79 and may be omitted. The hand pump 53 maybe used at any time so long as the valve windings S8 and 89 arede-energized. i

While I have shown what I believe to be the best embodiments of myinvention it will be apparent to those skilled in the art that variouschanges and modiications may be made therein without departing from thespirit and scope of the invention as defined in the appended claims.

What is claimed is:

l. In combination with an internal combustion engine having a hydraulicstarter for cranking said engine, an accumulator connected to saidstarter for supplying said starter with hydraulic pressure fluid forcranking operation thereof, and movable control means associated withsaid starter for controlling cranking operation thereof, the provisionof hydraulic cylinder means connected to said accumulator, said cylindermeans comprising piston means connected to said control means for movingsaid control means to control operation of said starter, valve meansincluded in said connection between said accumulator and said cylindermeans for controlling cranking operation lof said starter, meanscomprising an electromagnet and including an operating winding forcontrolling said valve means, said combination further comprising anenergizing circuit for said operating winding, and switch means includedin said energizng circuit for controlling said cranking operation ofsaid starter.

2. In combination with an internal combustion engine having a hydraulicstarter for cranking said engine, a hydraulic accumulator connected tosaid starter for supplying pressure fluid to said starter for crankingoperation thereof, a reservoir connected to said starter for receivingspent pressure uid therefrom, movable con- ,trol means associated withYsaid starter for controlling said cranking operation thereof, and pumpmeans for returning spent pressure fluid from said reservoir to saidaccumulator, the provision of hydraulically operated means connected tosaid control means for movement thereof, said hydraulically operatedmeans including resilient means yieldingly urging movement of saidcontrol means to maintain said starter inoperative, and valve meansactuable for selectively connecting said hydraulically operated meanseither to said accumulator or to said reservoir, said hydraulicallyoperated means, when connected to said accumulator by said valve means,moving said control means against said yielding action of said resilientmeans to cause cranking operation of said starter.

3. The combination according to claim 2, in which said hydraulicallyoperated means comprises a cylinder having a movable piston therein,said piston being connected to said control means, and said resilientmeans comprising spring means yieldingly acting on said piston and onsaid control means.

4. The combination according to claim 2, wherein said valve meanscomprises at least one valve including an electromagnet having anoperating winding for said selective actuation thereof, said combinationfurther comprising an energizing circuit for said operating winding andswitch means included in said energizing circuit for controlling saidcranking operation of said starter.

5. The combination according to claim 2, in which said valve meanscomprises at leastone valve including an electromagnet having anoperating winding for said selective actuation thereof, said combinationfurther comprising a normally energized power supply circuit to whichsaid winding is connected, said valve means maintaining saidhydraulically operated means connected with said reservoir duringcontinued energization of said power supply circuit.

6. The combination according to claim 5, wherein said pump meanscomprises a hand pump, said combination comprising the further provisionof manually operable valvemeans for maintaining said hydraulicallyoperated means disconnected from said accumulator during deenergizationof said power supply circuit and operation of said hand pump, saidmanually operable valve means permitting connection of saidhydraulically operated means to said reservoir. v

References Cited in the file of this patent UNITED STATES PATENTS1,028,364 Knight et al June 4, 1912 1,795,053 Strong Mar. 5, 19311,965,371 Drabelle July 3, 1934 2,467,067 Wilson Apr. 12, 1949 2,498,697Molyneux et al Feb. 28, 1950 2,802,452 Hogeman Aug. 13, 1957 FOREIGNPATENTS 942,178 Germany Apr. 26, 1956

